<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>test</title>
</head>
<body>
    <h1>我是标题内容</h1>
    <p id="myid" class="myclass">
        今天周五了！！！
    </p>
</body>
</html>
<script>
    var p = document.getElementById("info");
    p.innerHTML = "明天不用上班";
    document.write(p.innerHTML);
    document.write(p.innerText);
</script>